1. Field of the Invention
The present invention relates to an electrical connector, and particularly to a high density electrical connector having a plurality of circuit boards for high speed signal transmission.
2. Description of Related Art
With the development of communication and computer technology, high density electrical connectors with conductive elements in a matrix arrangement are desired to construct a large number of signal transmitting paths between two electronic devices. Such high density electrical connectors are widely used in internal connecting systems of severs, routers and the like devices requiring high speed data processing and communication.
These connectors generally comprise two mating connector halves, i.e., a plug connector connecting with a backplane and a receptacle connector connecting with a daughter card. The backplane and the daughter card are positioned in parallel or perpendicularity to each other. The mating connector halves of one type can be referred to Berg Product Catalog published on January 1998 which is submitted herewith by Information Disclosure Statement (IDS), and the website of Teradyne, Inc, at the following internet address: http://www.teradyne.com/prods/tcs/products/hpi/vhdm/modoconfig.html. A hard copy of the website is submitted herewith by IDS for reference. Each connector comprises an overmolded carrier made of dielectric material and multiple rows and columns of contacts. Each column of the contacts is provided as a separate module. Multiple modules are installed in the insulating carrier to form a complete connector. Generally, all of the modules are substantially identical. When it is desired to have different types of modules in the connector in order to meet different requirements of signal transmission, a problem is raised that additional tooling and handling are required for the different types of the modules, thereby increasing manufacturing cost.
U.S. Pat. No. 6,152,747, issued to Teradyne, Inc., discloses two mating connector halves of another type. Each connector disclosed therein comprises a dielectric housing defining a plurality of slots therein and a plurality of wafer-like modules retained in respective slots. Each wafer-like module includes a dielectric support and a plurality of signal and grounding contacts attached at its opposite sides, respectively. However, the connector of this type has difficulty in fulfilling the increasing demand of signal transmission of different electrical characteristics through the connector.
U.S. Pat. Nos. 6,267,604, 5,980,321, 6,293,827 and 6,299,484 each disclose an electrical connector providing a plurality of circuit boards to thereby achieve improved signal transmission of different electrical characteristics through the connector.
A connector disclosed in U.S. Pat. No. 6,267,604 comprises a front housing portion having a front wall with a plurality of parallel apertures extending therethrough, an organizer attached to the front housing portion and a plurality of individual circuit boards retained between the front housing portion and the organizer. The organizer has a plurality of spaced slots located corresponding to the apertures, and a plurality of openings communicating with the slots in a bottom wall thereof. The circuit boards have mating portions extending through the apertures of the front housing portion for mating with a complementary connector, and mounting edges received in the slots of the organizer. The mounting edges of the circuit boards have a plurality of terminals secured thereon by soldering. The terminals extend through respective openings of the organizer for electrically connecting with a circuit substrate.
However, the ""604 patent has the shortcoming that connecting the terminals to the circuit boards is complicate and time-consuming. Furthermore, once the terminals are connected with the circuit boards, the terminals cannot be separated from the circuit boards. If the terminals or circuit boards are damaged, both of them must be replaced together, thereby increasing the cost of production. In addition, when the circuit boards are assembled to the organizer, the terminals secured on the circuit boards need to be received in the respective openings of the organizer for fixing the terminals, thereby increasing the difficulty of assemblage of the circuit boards.
Hence, an improved electrical connector is required to overcome the disadvantages of the related art.
Accordingly, a first object of the present invention is to provide a high density electrical connector having a plurality of individual circuit boards easily and reliably retained therein.
A second object of the present invention is to provide a high density electrical connector having a plurality of wafers assembled together for receiving a plurality of individual circuit boards.
A third object of the present invention is to provide a wafer assembly for an electrical connector, each individual wafer having a plurality of signal contacts and a grounding member respectively mounted on its opposite sides for mechanically and electrically contacting with a corresponding inserted circuit board.
In order to achieve the objects set forth, a high density electrical connector in accordance with the present invention comprises a dielectric housing defining a plurality of parallel channels therein, and a spacer consisting of a plurality of wafers assembled together. A plurality of slots is defined between adjacent wafers. Each wafer includes a dielectric base and a plurality of signal contacts and a grounding member respectively mounted on opposite sides of the dielectric base. A plurality of circuit boards is retained between the housing and the spacer. Each circuit board has a mating portion aligned with a corresponding channel of the housing for mating with a complementary connector, and a mounting portion received in a corresponding slot of the spacer. The mounting portions of the circuit boards mechanically and electrically contact with the signal and the grounding conductive elements of the spacer.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.